[Xuefeng magnetite blog] python GUI job: tkinter control changes background color

Posted by Rony on Sat, 07 Dec 2019 22:12:10 +0100

Requirement

Use tkinter to generate the following window:

Enter a name in the text box in the upper right corner, select a number in the next drop-down box, click "click me!", and the text of "click me!" will be changed as follows:

You can select either Unchecked or Enabled.

Clicking on one of Blue, Gold or Red will change the background to the corresponding color.

The bottom text box can be used to enter text. When the number of columns exceeds the range, you can use the scroll bar operation.

Reference material

Reference code

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# Technical support: https://www.jianshu.com/u/69f40328d4f0 
# Technical support https://china-testing.github.io/
# https://github.com/china-testing/python-api-tesing/blob/master/practices/tk/tk1.py
# Project practical discussion QQ group 630011153 144081101
# CreateDate: 2018-11-27

import tkinter as tk
from tkinter import ttk
from tkinter import scrolledtext

win = tk.Tk()   

# Add a title       
win.title("Python GUI")  

# Modify adding a Label
a_label = ttk.Label(win, text="A Label")
a_label.grid(column=0, row=0)

# Modified Button Click Function
def click_me(): 
    action.configure(text='Hello ' + name.get() + ' ' + 
                     number_chosen.get())

# Changing our Label
ttk.Label(win, text="Enter a name:").grid(column=0, row=0)

# Adding a Textbox Entry widget
name = tk.StringVar()
name_entered = ttk.Entry(win, width=12, textvariable=name)
name_entered.grid(column=0, row=1)

# Adding a Button
action = ttk.Button(win, text="Click Me!", command=click_me)   
action.grid(column=2, row=1)                                 # <= change column to 2

# Creating three checkbuttons
ttk.Label(win, text="Choose a number:").grid(column=1, row=0)
number = tk.StringVar()
number_chosen = ttk.Combobox(win, width=12, textvariable=number, state='readonly')
number_chosen['values'] = (1, 2, 4, 42, 100)
number_chosen.grid(column=1, row=1)
number_chosen.current(3)

chVarDis = tk.IntVar()
check1 = tk.Checkbutton(win, text="Disabled", variable=chVarDis, state='disabled')
check1.select()
check1.grid(column=0, row=4, sticky=tk.W)                   

chVarUn = tk.IntVar()
check2 = tk.Checkbutton(win, text="UnChecked", variable=chVarUn)
check2.deselect()
check2.grid(column=1, row=4, sticky=tk.W)                   

chVarEn = tk.IntVar()
check3 = tk.Checkbutton(win, text="Enabled", variable=chVarEn)
check3.deselect()
check3.grid(column=2, row=4, sticky=tk.W)                     

# GUI Callback function 
def checkCallback(*ignoredArgs):
    # only enable one checkbutton
    if chVarUn.get(): check3.configure(state='disabled')
    else:             check3.configure(state='normal')
    if chVarEn.get(): check2.configure(state='disabled')
    else:             check2.configure(state='normal') 

# trace the state of the two checkbuttons
chVarUn.trace('w', lambda unused0, unused1, unused2 : checkCallback())    
chVarEn.trace('w', lambda unused0, unused1, unused2 : checkCallback())   


# First, we change our Radiobutton global variables into a list
colors = ["Blue", "Gold",  "Red"]   

# We have also changed the callback function to be zero-based, using the list 
# instead of module-level global variables 
# Radiobutton Callback
def radCall():
    radSel=radVar.get()
    win.configure(background=colors[radSel])

# create three Radiobuttons using one variable
radVar = tk.IntVar()

# Next we are selecting a non-existing index value for radVar
radVar.set(99)                                 
 
# Now we are creating all three Radiobutton widgets within one loop
for col in range(3):                             
    curRad = tk.Radiobutton(win, text=colors[col], variable=radVar, 
                            value=col, command=radCall)          
    curRad.grid(column=col, row=5, sticky=tk.W) 

# Using a scrolled Text control    
scr = scrolledtext.ScrolledText(win, width=30, height=3, wrap=tk.WORD)
scr.grid(column=0, columnspan=3)

name_entered.focus()      # Place cursor into name Entry

#======================
# Start GUI
#======================
win.mainloop()

Topics: Python github Lambda